In both fresh water and salt water fishing an angler utilizes tackle which typically includes a hook and sinker arrangement of some sort which are attached to a fishing line. There are a variety of systems for attaching hook and sinkers to a fishing line which include a direct in-line attachment to the fishing line or attachment of a "leader" which carries the hook and a sinker.
One of the minor discomforts of the pleasures of fishing is the loss of a hook and/or sinker as the result of an underwater obstacle or snag and the result and breakage of the fishing line. Typically, the fishing line has a lower breaking strength than a leader. In some instances the hooks and/or sinkers are attached to the leader by swivels and utilize high test strength special leader line and snap rings which can be used to attach hooks or sinkers. With the fancier leader rigs, the snagging of a hook or sinker typically can result in a breaking of the fishing line above the leader assembly with the loss of the entire leader rig together with a loss of patience of the angler.
When an underwater snag in a fishing operation does occur, the angler typically wants to save the entire rig and will try to release the hook or sinker from the snag and will lose valuable fishing time trying to release the snag to recover the leader rig because with the more expensive and complicated leader rigs, the angler does not wish to lose the entire rig because of a snag. In addition to cost, when the fishing line breaks above the leader rig, time is also lost in assembling an entire and complete new leader rig.